title: Reductions in the energy content of meals served in the Chilean National Nursery School Council Program did not consistently decrease obesity among beneficiaries.
abstract: In 2001, the Chilean National Nursery Schools Council Program reduced by 10% the energy content (approximately 418.7 kJ) of meals served to children to reduce obesity. We assessed the impact of this measure on obesity and stunting among beneficiaries 2-5 y old. The energy reduction was staggered over 3 y, allowing for a quasi-experimental design involving early (2001), mid (2002), and late (2003) intervention groups. Routine anthropometric measurements (approximately 64,000/y) taken from 1996-2005 were obtained from registries; obesity (BMI-for-age Z-score > or = 2 SD) and stunting (height-for-age Z-score < or = 2 SD) were defined using the 2006 growth standards. Segmented regression analyses were conducted by intervention group to contrast pre- and postintervention trends. Overall, obesity was high (15.9%), with levels consistently higher in fall and winter as reported in other studies. Preintervention obesity trends increased in the early group (P = 0.001) but decreased in the late intervention group (P = 0.02). The impact of the energy reduction on obesity was inconsistent, with reductions in the early group (P < 0.01) but with no change in mid and late intervention groups (P > 0.05). Stunting prevalence was almost as low as in the growth standard (3.2 vs. 2.3%) and decreased preintervention in all groups (P < 0.05). Stunting prevalence increased postintervention (P < 0.05) in all but the late intervention group, where there was no change. Despite a robust design and the ability to detect small seasonal changes in obesity, our analyses showed that the 10% energy reduction did not consistently decrease obesity. The intervention may have slowed improvements in linear growth, but concern is tempered by the near absence of growth failure.
authors.affiliation: Nutrition and Health Sciences Program, Graduate School, Emory University, Atlanta, GA 30322, USA.
authors.forename: Camila
authors.initials: C
authors.lastname: Corvalán
authors.forename: Ricardo
authors.initials: R
authors.lastname: Uauy
authors.forename: Rafael
authors.initials: R
authors.lastname: Flores
authors.forename: David
authors.initials: D
authors.lastname: Kleinbaum
authors.forename: Reynaldo
authors.initials: R
authors.lastname: Martorell
mesh_terms: D017677:Age Distribution; D002664:Child Nutritional Physiological Phenomena; D002669:Child Welfare; D002675:Child, Preschool; D002677:Chile; D004045:Dietary Services; D002149:Energy Intake / Q000502:physiology*; D005260:Female; D006293:Health Promotion; D006801:Humans; D008297:Male; D009751:Nutritional Requirements; D009752:Nutritional Status; D009765:Obesity / Q000517:prevention & control*; D012727:Sex Characteristics; D012959:Socioeconomic Factors